Enameling support and process of use



ENAMELING SUPPORT AND PROCESS OF USE Filed Aug. 18, 1932 Ila-E INVENTOA B i Y M7 M4) F 4 f; ,4 TTORNE) i?atented Nov. 1 4, 1%33 rise STATES ENAMELING SUPPORT AND PROCESS OF USE Henry Trenkamp,

land, Ohio Application August 18,

13 Claims.

My invention pertains to an enameling support and the process of its use. More particularly, the invention is designed to simplify, expe dite and cheapen the procedure of enameling stamped metal articles which either had become distorted from their intended'shape or would be likely to become distorted subsequently by the enameling process.

While my invention is applicable to many forms of articles, I have elected to exemplify the application of its principles to semi-cylindrical halves of a water heater casing which the company with which I am associated has for sometime very successfully enameled in large num- 15 bers.

Water heater jackets were long made of cast iron, but of late years have been superseded by a stamped metal form. J apanning and other sulficiently economical metal coatings proved unsatisfactory for thin metallic jackets because of exposure to the heat of the burner. consequent ly, enamel coatings have rapidly come into vogue and become established as an improvement even aside of the attractive range of colorselection, but one very troublesome handicap has presented a problem which my invention has happily solved.

Stamped sheet metal products of arcuate or concavo -convex formattend to assume a distorted 9 form after being stamped and die-released and such an occurrence has proved very troublesome when two or more of such stamped parts were to be assembled. For. instance, the pair of semicylindrical water heater casing parts so widely varied from uniformityas to greatly hinder their hinged connection and as to prevent the de-- sirably accurate interfitting of the other pair of longitudinal edges. Moreover, even when the stamped articles had not been enough distorted for rejection, they frequently suffered further distortion after the enameling process. In consequence, there was a prohibitively high percentage of-rejections.

Instead of employing as heretofore the pronged fixture for minimizing contact with the enamel coating why employ a special templet support designed to restore the desired shape of the stamped article by confining resilient edges thereof and to maintain the desired shape during 9 the enameling procedure? Instead of using upstanding prongs or substantially horizontal approximate knife edges, my templet not only supports on horizontally disposed knife edges, but confines by appositioned lip-right knife edges which collectively conform to the desired contour-Which the finished article is to have.

The object of my invention has been to elimi-.

hate the stated difficulties and has proved highly successful because realizing the following advantages Jia, Shaker Heighta'Ohio, assignor to The Ohio F oundry Company, Cleve- 1922. Serial No. 629,320

I. Avoidance of need of lining up the stamped products or resilient edges thereof.

2. Erevention oi weave distortion during enameling. g r

3. Interchangeability of duplicated parts.

4. Reduced assembly cost.

5. Possibility of employing a lighter gauge stock which by other methods would multiply the distortion hazard. r

It is to be realized that the scope of my invention comprehends many equivalent methods and constructions. The showing of the drawing and the particular description are merely a specific exemplification.

Adverting to the drawing:

Fig. 1 is a top plan view of an enameling support.

Fig. 2 is a sectional view on line 22 of Fig. 1.

Fig. 3 is a top plan View showing a semi-cylindrical article supported upon the support.

Fig. 4; is a sectional view on line 4-4 of Fig. 3 and further showing in dotted lines an expended form of the article prior to being compressed for fitted deposition within the confines of the support.

Fig. 5' is an enlarged detail View of the supporting knife edges.

My support includes longitudinal side members 1, connecting end members 2 and an intermediary connecting brace 3. The composite base portion, composed of the members 1, 2, and 3 is optionally provided all the way around with an upstanding stiifening rib 4. Such an enamel support is customarily formed of some suitable alloy capable of resisting high temperatures Without warpage. One end of the support has projecting upwardly from each of its members 1 a pair of spaced prongs 5, which are alined crosswise in pairs and of which each pair is spaced apart a like distance as clearly appears in'Fig. 1. Similarly, the two opposite ends of the members 1 each carries a pair of upright prongs 6 which are likewise alined crosswise in pairs, but the crosswise pairs of which happen to be somewhat less far apart whereas either pair of the prongs 6 on any one member I happen to befarther apart longitudinally than the pair of prongs 5 on either one of the members 1. Itis to be understood that the number of prongs and their spacing both longitudinally and crosswise is purely a matter of selection depending upon, the size and shape of the particular article which is to be enameled.

Each prong has that one of its upper corners which is appositioned with respect to another prong, formed as an L shaped knife edge to comprise the edges enlarged view of Fig. 5. The employment of sharp edges for supporting articles which have been enamel coated is common practice in the art, but I believe I haveoriginated the coopera- 7 and 8 as clearly shown in the tical knife edge 8.

tion of angularly related knife edges predeterminably spaced with reference to those of another row of supporting edges.

The drawing exemplifies a fixture adapted for use as a templet for one half of the cylindrical jacket of a water heater, such a jacket being formed of two stamped metal halves 9, the longitudinal edges of which are doubled back to form a reenforced edge 10 as clearly appears in Fig. 5. However, articles which have been stamped to arcuate or concavo-convex form are subject to slight distortion (usually somewhat expanded as shown in Fig. 4). Consequently, if they were to be enameled while of any distorted shape, they would not fit each other and would cause a large per cent. of rejections by the purchaser.

It will be observed that the pairs of prongs 5 and the pairs of prongs 6 are spaced apart to conform at the desired width of the jacket halves which may be readily sprung from the dotted line position shown in Fig. 4 to the full line position there appearing. When so sprung into position, the edges 10 will be laterally confined by the ver- Thereby the enamel coated semi-cylindrical article is restored to its proper shape which it will maintain after having been burned. For most colors a single ground coat when burned at a temperature of about 1700 degrees Fahrenheit proves satisfactory, but the ivory color, for instance, requires not only a ground coat which is burned on but subsequently additional sprayed coats. The practice accord ing to my invention permits further applications of sprayed coatings with security as to the proper shape or size of the article which has been previously supplied with a baked ground coat.

I claim:--

1. The process of supporting and burning a concavo-convex resilient metal article, comprising, fitting edges of the freshly enamel-coated article between spaced prongs of a templet adapted to withstand high heat without distortion and then burning the article while so confined.

2. The process of supporting and burning an arched approximately semi-cylindrical metal article having resilient edge portions, comprising, fitting longitudinal edges of the freshly enamelcoated article between two rows of longitudinally spaced prongs of a templet adapted to withstand high heat without distortion and then burning the article while so confined.

3. The process of supporting and burning an arched approximately semi-cylindrical metal article having resilient edge portions, comprising, fitting longitudinal edges of the freshly enamelcoated article between two rows of longitudinally spaced converging-knife-edged ledges of a templet for supporting and laterally confining said edges while leaving air spaces at the junctions of said knife edges and then first burning said article in a high temperature oven and subsequently allowing said article to cool, both while its edges are so supported and confined.

4. An enamel-burning support comprising spaced rows of ledges defined by converging approximate knife edges.

5. An enamel-burning support comprising appositioned ledges of like elevation but spaced apart varying distances.

6. Anenamel-buring support comprising spaced rows of ledges, the ledges of each row being defined by a bottom edge and a meeting edge extending upwardly from the far end of the bottom edge with reference to the other row.

7. An article of the character described for use as a supporting templet for a distortable article to be enameled, comprising a base, and a row of upstanding projections on opposite sides of said base, near upper corner portions of said projections being cut away whereby collectively to define a composite rest conforming to the desired shape of the portions of said article required to be supported thereby.

8. An article of the character described for use as a supporting templet for a distortable article to be enameled, comprising a reticulated base, and a row or" symmetrically arranged upward projections on opposite sides of said base, appositioned upper corner portions of said'projections being cut away whereby to define laterally confined pairs of rests intended collectively to conform to the desired shape of the portions of said article required to be supported thereby.

' 9. An article of the character described for use as a supporting templ t for a semi-cylindrical stamping to be enameled, comprising a base, and a row of upstanding projections on opposite sides of said base, the projections in one row being alined crosswise with those of the other row, appositioned upper corner portions of said projections being notched to form converging edge portions whereby such portions are adapted collectively to prescribe and maintain the shape of a stamping fitted thereagainst.

10. The process of supporting and burning a color-coated, resilient metal stamping subject to warpage under temperature change, comprising, causing opposite edge portions of said stamping gravitationally to rest upon predeterminately spaced ledges of a templet, confining said edge portions against displacement relatively to each other and then while so supported subjecting said templet and stamping to burning heat and allowing both to cool.

11. The process of supporting and burning a.

resilient concave-convex metal article, comprising supporting said article on marginal edge portions thereof by effecting slight constriction of said article and by deposition of said edge portions in the corners of appositioned pairs of templetforming angular ledges, subjecting to heat and then allowing the article to cool while so confined.

12. A burning-oven fixture fashioned with a plurality of separated predeterininately spaced ledges extending along one side of the fixture and fashioned with a plurality of separated predeterminately spaced ledges extending along the opposite side of said fixture, said ledges each being fashioned as a recess with its entry presented diagonally upward and across toward the other side of the fixture.

13. A burning-oven fixture fashioned with a plurality of separated predeterminately spaced ledges extending along one side of the fixture and fashioned with a plurality of separated predeterminately spaced ledges extending along the op posite side of said fixture, the ledges along one side being appositioned each with respect to a ledge along the other side and said pairs of ap-' 

